Methods and systems are known for making various measurements of liquids within containers, including those that measure or indicate liquid level or volume by the use of a float, and those that weigh the liquid together with its container of known weight. However, the known systems are usually relatively complicated or are limited as to the types of applications in which they may be conveniently and accurately used. For example, the accuracy provided by a liquid measuring system that weighs the liquid together with its container is inherently limited by the additional component of the container's weight in the initial output of the system. An exemplary embodiment of a prior art float system is disclosed in U.S. Pat. No. 2.096,411 to St. John et al. Float systems generally require the use of guide wires within the container to position the float, and often require a significant amount of maintenance to keep the measuring system operational. Moreover, liquid measuring systems that use floats may not be well-suited for applications involving pressure vessels due to the affect of the pressure on the floats.
Consequently, as a result of these and other disadvantages in the prior art systems, a need exists for improved liquid level indicating methods and systems.